Malaria is common in areas such as Africa, South America, and Southern Asia. This medicine is not effective against all strains of malaria. Patient assistance program for plaquenil Plaquenil dosage 400 mg Mechanism of action of hydroxychloroquine as an antirheumatic drug. Fox RI1. Author information 1Department of Rheumatology, Scripps Clinic and Research Foundation, La Jolla, CA 92037. The antimalarial agents chloroquine and hydroxychloroquine have been used widely for the treatment of rheumatoid arthritis and systemic lupus erythematosus. Mechanism of action The precise mechanism by which hydroxychloroquine exhibits activity against Plasmodium is not known. Hydroxychloroquine, like chloroquine, is a weak base and may exert its effect by concentrating in the acid vesicles of the parasite and by inhibiting polymerization of heme. Mechanism of action. Drugs that prolong QT interval and other arrhythmogenic drugs PLAQUENIL prolongs the QT interval and should not be administered with other drugs that have the potential to induce cardiac arrhythmias. Also, there may be an increased risk of inducing ventricular arrhythmias if PLAQUENIL is used concomitantly with other. Taking hydroxychloroquine long-term or at high doses may cause irreversible damage to the retina of your eye. Hydroxychloroquine is also an antirheumatic medicine and is used to treat symptoms of rheumatoid arthritis and discoid or systemic lupus erythematosus. Plaquenil drug action Hydroxychloroquine Plaquenil Side Effects & Dosage for Malaria, Plaquenil - FDA prescribing information, side effects and uses Hydroxychloroquine actavis PDR Drug Summaries are concise point-of-care prescribing, dosing and administering information to help phsyicans more efficiently and accurately prescribe in their practice PDR's drug summaries are available free of charge and serve as a great resource for US based MDs, DOs, NPs and PAs in patient practice Plaquenil hydroxychloroquine sulfate dose, indications.. Plaquenil Concordia Pharmaceuticals Inc. FDA Package Insert. Mechanisms of action of hydroxychloroquine and chloroquine.. Side Effects. Drug information provided by IBM Micromedex Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Before using Plaquenil, tell your doctor if you are allergic to any drugs, or if you have psoriasis, porphyria, liver disease, alcoholism, or glucose-6-phosphate dehydrogenase G-6-PD deficiency. Take Plaquenil for the full prescribed length of time for malaria. Your symptoms may improve before the infection is completely cleared. Hydroxychloroquine is a quinoline medicine used to treat or prevent malaria, a disease caused by parasites that enter the body through the bite of a mosquito. Malaria is common in areas such as Africa, South America, and Southern Asia.